• Journal of Korean Society of Water and Wastewater
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• v.32 no.5
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• pp.453-460
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• 2018

The impact of sodium hydroxide, which is one of chemicals of clean in place (CIP) for removing membrane fouling, on the PVDF membrane is reviewed with respect to physical/chemical structural change, the permeability affected therefrom. Based on the cleaning concentration applied in membrane water treatment facilities, 10% of accumulated defluorination was confirmed up to 166g.hr/L which reflects the exposure time. However, membrane resistance was confirmed to be reduced by about 10%. Through FT-IR and EDS analysis, reduction of F and change of are confirmed as factors that affect the permeability of membrane. Membrane resistance, which affects permeability, is affected by loss of additives for hydrophilicity, rather than defluorination of PVDF material. Therefore, in order to check membrane degradation degree, an accelerated test by NaOH was carried out, loss of additives was confirmed, and then PVDF inherent characteristic was observed.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.8
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• pp.309-321
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• 2020

This study aims to examine the effects of strategic management accounting on firm performance of finance businesses in Thailand. Strategic management accounting comprises of environmental scanning, competitor orientation and forward-looking information. In this study, 175 finance businesses in Thailand are the samples of the study. A mail survey procedure was used for data collection. The hierarchical multiple regression analysis is employed to test the research relationships. Firstly, environmental scanning positively affects operational excellence, organizational effectiveness and firm performance. Secondly, competitor orientation is positively related to managerial efficiency and organizational effectiveness. Thirdly, forward-looking information has a positive influence on operational excellence, managerial efficiency, organizational effectiveness, and firm performance. In addition, operational excellence, managerial efficiency and organizational effectiveness have positive impact on firm performance. Finally, to verify the mediating effects, operational excellence, managerial efficiency and organizational effectiveness are the mediators of the research relationships. This study confirms that all dimensions of strategic management accounting play a significant role in determining business outcome as being congruent with the theory of resource-based views of the firms. Executives of firms need to provide valuable resources and capabilities to support the strategic management accounting implementation in order to achieve good business outcome in highly competitive environments.

• Wind and Structures
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• v.21 no.5
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• pp.537-564
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• 2015

Excessive motions in buildings cause occupants to become uncomfortable and nervous. This is particularly detrimental to the tenants and ultimately the owner of the building, with respect to financial considerations. Serviceability issues, such as excessive accelerations and inter-story drifts, are more prevalent today due to advancements in the structural systems, strength of materials, and design practices. These factors allow buildings to be taller, lighter, and more flexible, thereby exacerbating the impact of dynamic responses. There is a growing need for innovative and effective techniques to reduce the serviceability responses of these tall buildings. The current study considers a case study of a real building to show the effectiveness and robustness of the TLD in reducing the coupled lateral-torsional motion of this high-rise building under wind loading. Three unique multi-modal TLD systems are designed specifically to mitigate the torsional response of the building. A procedure is developed to analyze a structure-TLD system using High Frequency Force Balance (HFFB) test data from the Boundary Layer Wind Tunnel Laboratory (BLWTL) at the University of Western Ontario. The effectiveness of the unique TLD systems is investigated. In addition, a parametric study is conducted to determine the robustness of the systems in reducing the serviceability responses. Three practical parameters are varied to investigate the robustness of the TLD system: the height of water inside the tanks, the amplitude modification factor, and the structural modal frequencies.

• Journal of the Korean Institute of Landscape Architecture
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• v.21 no.4
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• pp.83-99
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• 1994

To compare basic information and to inspect impacts situations between 1987 and 1992, this study was executed in Chongnung valley of Mt. Puk'an. And to provide basic informations through the change of plant species diversity, some methods were applied and analyzed such as the degree of environmental impacts and belt-transect method. The results were summarized as follows; 1. In order to find environmental impacts by visitor, the degree of environmental impacts class that was proposed by Kwon(1991) was implicated. In 4 sites, total area of over impact class 2 is 86,692$m^2$ and area of impacts class 4-6 that is impossible to recover naturally is 36,856$m^2$. Totally, the impacted area was profounded qualitatively and quantitatively against 1987's. 2. In the vegetation change by visitor's impacts, species diversity was rapidly decreased as nearer the campsite and trail. And in the basal area and coverage, lower layer species was sensitively changed. Trampling-resistent species is as following; Robinia pseudoacacia, Lespedeza cyrtobotrya, Staphylea bumalda, Clerdendron trichotomum, Stephanandra incisa, Rubus crataegifolius, Lespedeza maximowiczii, Weigela subsessilis, Rosa multiflora, Zanthoxylum schinifolium, Lindera obtusiloba, Callicarpa japonica, Sorbus alnifolia, Symplocos mongolica and so on. In the results of soil hardness test, that was decreased as far away from campsite and trail. 3. In the 4 sites selected in Chongnung valley of Puk'ansan Natioal Park, management plans was largely divided 4 category, such as trail improvement, facilities setting, ecotone vegetation establishment, and vegetation rehabilitation. And a suggestion was provided to each site.

• Knowledge Management Research
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• v.20 no.1
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• pp.231-249
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• 2019

Technology transfer from a multinational company to a local subsidiary is essential for successful local market operations. This study aims to analyze the impact of market, cultural and institutional environmental factors on international technology transfer and innovation performance based on the S-C-P paradigm. We collected data from one hundred ninety-five subsidiaries of Korean parent firms located in seventeen countries and used structural equation modeling to test hypotheses. The analysis findings are as follow; First, both market and cultural environment directly affect international technology transfer. However, institutional environment such as protection of intellectual property does not affect international technology transfer. Due to the less risk of technology disclosure involved in technology transfer within the MNE organization can be not relationship between protection of intellectual property in the host country and the foreign subsidiary's transfer of technology. The risk of infringement of intellectual property is relatively low in intra-firm transfer of technology. Second, the technology introduced from the parent company has a positive effect on the innovation performance of local subsidiaries. This implies that multinational companies that have entered unfamiliar overseas markets should be able to effectively transfer the inherent advantages of the parent company to their overseas subsidiaries, and that their ability to adapt to the local environment is important.

• Nuclear Engineering and Technology
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• v.53 no.4
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• pp.1331-1344
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• 2021

This study is to evaluate the seismic capacity of the fire-damaged cabinet facility in a nuclear power plant (NPP). A prototype of an electrical cabinet is modeled using OpenSees for the numerical simulation. To capture the nonlinear behavior of the cabinet, the constitutive law of the material model under the fire environment is considered. The experimental record from the impact hammer test is extracted trough the frequency-domain decomposition (FDD) method, which is used to verify the effectiveness of the numerical model through modal assurance criteria (MAC). Assuming different temperatures, the nonlinear time history analysis is conducted using a set of fifty earthquakes and the seismic outputs are investigated by the fragility analysis. To get a threshold of intensity measure, the Monte Carlo Simulation (MCS) is adopted for uncertainty reduction purposes. Finally, a capacity estimation model has been proposed through the investigation, which will be helpful for the engineer or NPP operator to evaluate the fire-damaged cabinet strength under seismic excitation. This capacity model is presented in terms of the High Confidence of Low Probability of Failure (HCLPF) point. The results are validated by the proper judgment and can be used to analyze the influences of fire on the electrical cabinet.

• Environmental and Resource Economics Review
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• v.18 no.3
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• pp.523-544
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• 2009

The purpose of this paper is to estimate the impact of foreign direct investment on environmental performance for 27 OECD countries using endogenous environmental policy model. The empirical test shows that with 1% increase in the ratio of inflow stock of foreign direct investment over domestic capital stock, emission on NOx and $CO_2$ will increase by 0.0071%(NOx) and 0.0165%($CO_2$) and 1% increase in the ratio of foreign capital stock induces 0.044%(fixed effect) and 0.047%(random effect) of economic growth. 1% increase of per labor total output increases 2.038%(fixed effect) or 1.890%(random effect) in reinforcement of environmental regulation. However, we could not confirm the Porter's hypothesis that the more strong environmental regulation leads technical innovation. The scale effects (0.0119, 0.0172) are estimated higher than the technical effects (-0.0048, -0.0007) in two pollutants (NOx, $CO_2$). It implies that each country needs to increase pollution abatement and control expenditure more aggressively to protect environment.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.6
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• pp.649-655
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• 2005

Automotive exhaust is suspected to be one of the main reasons of the rapid increase in greenhouse effect gases in ambient air. Although methane emissions are generally orders of magnitude lower than emissions of $CO_{2}$, the global warming potential (GWP) of methane is greater than that of $CO_{2}$. The environmental impact of methane emissions from vehicles is negligible and is likely to remain so for the foreseeable future. In this study, in order to investigate greenhouse gas emission characteristics from gasoline passenger cars, 20 vehicles were tested on the chassis dynamometer and methane emissions were measured. The emission characteristics by model year, mileage, vehicle speed were discussed. Test mode is CVS-15 mode that have been used to regulate for light-duty vehicle in Korea. It was found that $CH_{4}$ emissions showed higher for cold start, old model year and long mileage than hot start, new model year and short mileage, respectively. These results were compared with IPCC emission factors and the overall our results were anticipated to contribute for domestic greenhouse gas emissions calculation.

• Structural Engineering and Mechanics
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• v.51 no.5
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• pp.755-771
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• 2014

Environmental changes, especially global climate change, are creating new challenges to the development of the Arctic regions, which have substantial energy resources. And attention to offshore structures has increased with oil and gas development. The structural impact response of an explosion-resistant profiled blast walls normally changes when it operates in low temperatures. The main objectives of this study are to investigate the structural response of blast walls in low temperature and suggest useful guidelines for understanding the characteristics of the structural impact response of blast walls subjected to hydrocarbon explosions in Arctic conditions. The target temperatures were based on the average summer temperature ($-20^{\circ}C$), the average winter temperature ($-40^{\circ}C$) and the coldest temperature recorded (approximately $-68^{\circ}C$) in the Arctic. The nonlinear finite element analysis was performed to design an explosion-resistant profiled blast wall for use in Arctic conditions based on the behaviour of material properties at low temperatures established by performing a tensile test. The conclusions and implications of the findings are discussed.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.2_2
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• pp.333-340
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• 2023

Environmental regulations are being strengthened worldwide to solve global warming. For this reason, interest in eco-friendly gas fuels such as LNG and hydrogen is continuously increasing. However, when adopting eco-friendly gas fuel, liquefying at a cryogenic temperature is essential to ensure economic feasibility in storage and transportation. Although austenitic stainless steel is typically applied to store cryogenic liquefied gas, structural steel can experience sudden heat shrinkage in the case of leakage in the loading and unloading process of LNG. In severe cases, the phase of the steel may change, so care is required. This study conducted Charpy impact tests on steel material in nine different temperature ranges, from room to cryogenic temperatures, to analyze the effects of cryogenic liquefied gas leaks. As a result of the study, it was not easy to find variations in ductile to brittle transition temperature (DBTT) due to the leakage of cryogenic liquefied gas. Still, the overall impact toughness tended to decrease, and these results were verified through fracture surface analysis. In summary, brittle fracture of the steel plate may occur when a secondary load is applied to steel for hull structural use exposed to a cryogenic environment of -40 ℃ or lower. Therefore, it needs to be considered in the ship design and operating conditions.